Here is my code:
serialNumbers = "";
String[] serialArray = serialNumbers.split(",");
int arrayLength = serialArray.length;
arrayLength is showing 1 even there have no value in serialArray. I was expecting that length should return 0 in this case.
From the doc:
If the expression does not match any part of the input then the resulting array has just one element, namely this string.
Note that this doc is from the String.split(String, int) method, which is invoked from String.split(String)
String.split(), so it's a useless test. What's the actual problem you're trying to solve?String.split to do? What's the purpose behind the check?Split always returns at least one element.
In the case that a separator is not found, the entire input is returned in a single-element array.
serialArray contains [""], which is 1 element
If you look at the implementation of String.class (refer snippet below). Here off shows the match count and this is the String currently being processed for split operation and you have ur string as serialNumbers = "";. Thats why it is returning one item in array.
// If no match was found, return this if (off == 0) return new String[]{this};
public class TestArgs {
public static void main(String[] args) {
String checkString = "";
System.out.println("" + splitString(checkString));
}
public static int splitString(String checkString) {
if (checkString.indexOf(",") != -1 || !"".equals(checkString)) {
System.out.println("hello " + checkString.split(",").length);
return checkString.split(",").length;
} else {
return 0;
}
}
}
,. How many results would you expect it to return, then? When you answer that, I think you'll understand why this returns 1.